1 /* 2 * Copyright (C) 2014 The Android Open Source Project 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in 12 * the documentation and/or other materials provided with the 13 * distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 #ifndef _RESOLV_NETID_H 29 #define _RESOLV_NETID_H 30 31 /* This header contains declarations related to per-network DNS 32 * server selection. They are used by system/netd/ and should not be 33 * exposed by the C library's public NDK headers. 34 */ 35 #include <sys/cdefs.h> 36 #include <netinet/in.h> 37 #include <stdio.h> 38 39 /* 40 * Passing NETID_UNSET as the netId causes system/netd/server/DnsProxyListener.cpp to 41 * fill in the appropriate default netId for the query. 42 */ 43 #define NETID_UNSET 0u 44 45 /* 46 * MARK_UNSET represents the default (i.e. unset) value for a socket mark. 47 */ 48 #define MARK_UNSET 0u 49 50 __BEGIN_DECLS 51 52 struct addrinfo; 53 54 #define __used_in_netd __attribute__((visibility ("default"))) 55 56 /* 57 * A struct to capture context relevant to network operations. 58 * 59 * Application and DNS netids/marks can differ from one another under certain 60 * circumstances, notably when a VPN applies to the given uid's traffic but the 61 * VPN network does not have its own DNS servers explicitly provisioned. 62 * 63 * The introduction of per-UID routing means the uid is also an essential part 64 * of the evaluation context. Its proper uninitialized value is 65 * NET_CONTEXT_INVALID_UID. 66 */ 67 struct android_net_context { 68 unsigned app_netid; 69 unsigned app_mark; 70 unsigned dns_netid; 71 unsigned dns_mark; 72 uid_t uid; 73 } __attribute__((packed)); 74 75 #define NET_CONTEXT_INVALID_UID ((uid_t)-1) 76 77 struct hostent *android_gethostbyaddrfornet(const void *, socklen_t, int, unsigned, unsigned) __used_in_netd; 78 struct hostent *android_gethostbynamefornet(const char *, int, unsigned, unsigned) __used_in_netd; 79 int android_getaddrinfofornet(const char *, const char *, const struct addrinfo *, unsigned, 80 unsigned, struct addrinfo **) __used_in_netd; 81 /* 82 * TODO: consider refactoring android_getaddrinfo_proxy() to serve as an 83 * explore_fqdn() dispatch table method, with the below function only making DNS calls. 84 */ 85 int android_getaddrinfofornetcontext(const char *, const char *, const struct addrinfo *, 86 const struct android_net_context *, struct addrinfo **) __used_in_netd; 87 88 /* set name servers for a network */ 89 extern void _resolv_set_nameservers_for_net(unsigned netid, 90 const char** servers, int numservers, const char *domains) __used_in_netd; 91 92 /* flush the cache associated with a certain network */ 93 extern void _resolv_flush_cache_for_net(unsigned netid) __used_in_netd; 94 95 /* delete the cache associated with a certain network */ 96 extern void _resolv_delete_cache_for_net(unsigned netid) __used_in_netd; 97 98 /* Internal use only. */ 99 struct hostent *android_gethostbyaddrfornet_proxy(const void *, socklen_t, int , unsigned, unsigned) __LIBC_HIDDEN__; 100 int android_getnameinfofornet(const struct sockaddr *, socklen_t, char *, size_t, char *, size_t, int, unsigned, unsigned) __LIBC_HIDDEN__; 101 FILE* android_open_proxy(void) __LIBC_HIDDEN__; 102 103 /* delete the cache associated with a certain network */ 104 extern void _resolv_delete_cache_for_net(unsigned netid); 105 106 __END_DECLS 107 108 #endif /* _RESOLV_NETID_H */ 109